This invention relates to a compression molding equipment, and more particularly, to a portable manually-operated hydraulic press used for mounting metallurgical specimens in a plastic mount.
Metal specimens which are to be examined metallographically are mounted in a plastic sample or mount wherein the specimen is embedded in the plastic with one side exposed for examination. The sample is prepared by placing the specimen in a molding press, adding the plastic mounting material and curing the plastic under pressure with heat.
The prior art molding presses include a hydraulic jack which provides the pressure for the molding. However, in order to provide the necessary pressure, these presses have had long jack operating handles, positioned at the bottom of the press, in order to achieve the necessary mechanical advantage to operate the jack. These long handles have caused stability problems in that under some conditions the operator could pull on the handle and cause the entire press to tip forwardly toward the operator. Furthermore, more women have become metallurgical technicians and have found these prior art presses difficult to use.
It is therefore an object of this invention to provide a press having a force application system which avoids the stability problems of the prior art presses and which is easier to use.
The prior art presses also require constant attention and repetitive pumping of the jack during the molten stage when the thermoplastic or thermosetting resin is changing from a powder to a viscous liquid in order to maintain the molding pressure.
It is therefore another object of this invention to provide an inexpensive, compact laboratory press of relatively simple design and construction that eliminates repumping of the press during the molten stage of the resin and requires a minimum of operator attention.
The foregoing and other objects and advantages will be apparent from the following description and appended claims. taken in conjunction with the drawings.